turn I'd reraise more~~~maybe miniraise is also OK
this guy reraised u pf and he bet flop and turn,there's no doult he got an overpair like QQ KK AA,he jgot only 4 outs to make his FH,so I think maybe miniraise's not a bad idea here

I fold river though it's really hard to~~~I don't think he would bet 3/4 pot with out a better hand while there's possiblely a flush

Preflop is fine given how deep you are, you're going to be looking at KK+ almost always when you get 5bet, so unless you have reason to believe he's 3betting pretty wide it's probably better to flat in position to avoid trouble.

Flop is fine, he's mostly repping big pocket pairs, whiffed stuff that we beat and maybe some medium pocket pairs, but since we have no idea how much fold equity we have against big pairs (i suspect very low at microstakes even deep) it's not so good to raise there and possibly get shoved on for a flip with 300bb stacks. Calling in position to try and release our equity seems better.

I'd raise more on the turn to make sure i can comfortably shove the river while laying him good odds, 3x the turn lets us shove for about 2/3 pot on the river, which i think is good.

The river is sadly a fold, i think he always has some sort of pocket pair when he makes that bet, so even tho it's hard it's a pretty clear fold in my mind.